Central Kuril Island Tsunami in Crescent City, California (11/15/2006)
On Wednesday, November 15, 2006 at 11:14:16 (UTC) a large (Mw = 8.3) earthquake occurred on the Kuril Islands Subduction Zone. The event caused a Pacific wide tsunami which was expected to reach Japan in 64 minutes and California in 8 hours and 20 minutes.
The first wave arrived at Hanasaki, Hokaido with an amplitude of 30 cm. After the observation of this minor tsunami in Japan, a large tsunami was not expected in Alaska or along the US west coast.
However, around 11 am PST, the Crescent City, California Harbor Control and Emergency offices received a warning for possible strong tsunami surges which were expected to arrive around 11:30 am. Because the tsunami effect was expected to be relatively minor, a full evacuation was not ordered, but rather targeted verbal warnings were issued for people in the harbor. Mr. Erik Macee from the fishing vessel 'Resolution' confirmed that he was warned by the harbor control at around 11:10 am.
The first wave arrived as expected but it was not noticed by the harbor control. Mr. Macee said he was in his boat when he first noticed the withdrawal. He was able to watch the tsunami from his boat looking at the water elevation change at the piling and breakwater.
The tsunami surges did not cause any damage until after 2 pm. Mr. Macee said the largest waves arrived around 2 or 2:30 pm. The second in the series of larger waves did the most damage when mooring lines from vessels berthed at Dock H were severed. Dock H had three boats, including the biggest boat in the harbor, 'Delana'. The 'Delana' was connected directly to the piling, while the other two vessels were connected to the exposed dock. The dock could not resist the strong current and the pull coming from the boats and failed
The current was so strong, harbor facilities manager Pual McAndrews reported that a white buoy at the entrance of the harbor was buried under water as the current flowed out of the harbor. He also noted that harbor seals and sea lions were not able to swim against the current.
Other witnesses described the tsunami in the harbor as 'flowing like a river'. It caused a whirlpool effect and it was flowing in clockwise direction. Dock H was the first dock in the flow direction and could not resist the flow.
After the Dock H, it was just a matter of time before Dock G failed. The loose boats carried pieces of Dock H when they crashed into Dock G and later into Dock F. A large portion of Dock F was also damaged, but it did not move around as did Docks G and H.
Docks E, F and G are used for small craft and sail boats. 'Windrose' and 'Allarion' are two of the sail boats that use Dock G. Robert Nunneley and Jim Herriott, owners of the vessels, learned about the tsunami and arrived at the harbor around 3:40 pm. They noticed that the currents were still very strong. Their boats Windrose and Allarion were pushed on to the other boats at Dock C. The Coast Guard helped them to move the boats from Dock C to F.
Sam and Kathleen Burke, who work at a local RV camp, returned to the campground around 2:30 pm. They noticed that the tide level was different than what would be expected for that time. They also observed several water level changes. Mrs. Burke measured the time between wave crests to be 12 min. She repeated this for three more waves to confirm her observation.
Public works technician Kevin Tupman came to north harbor around 2:40 pm. He also observed the changes in water level due to the tsunami. Mr. Tupman estimated the distance from the low water mark to the high water mark was some 850 ft. He was at the north harbor from 3 until 4 pm and he saw three full wave cycles, which confirms Mrs. Burke's observation.
Fortunately it was low tide when the tsunami surges first arrived around 11:30 am. Total damage in the harbor is expected to be between $500,000 to $1,000,000. Had the tide been high at the time of tsunami arrival the damage could have been more severe.
We modelled the Kuril Island tsunami in Crescent City Harbor. Our preliminary simulations match fairly well with the tide gauge record from this event. We get a good match for tsunami arrival time and for the overall wave period. Our simulations also suggest that later crests in the tsunami wave train would be the largest and possibly most damaging. Our numerical results also suggest that long period oscillations would be present in the harbor.
Wave height distribution around Crescent City and Del Norte County from the 2006 Kuril Island Tsunami.
Animation of the tsunami arriving in Crescent City and Northern California
Pictures provided by Prof. Lori Dengler, Humboldt State University.
Left: Aerial photograph of the Crescent City Harbor. Photo provided by Harbor Master Richard Young (taken by Rick Hiser). Right: GIS measurement of inundation distance between high and low water levels during the tsunami. Information provided by Mr. Kevin Tupman.
Pictures taken by Emergency Services Coordinator Allen Winogradov during the tsunami event.